gcc -L / -l option flags

gcc -l links with a library file.

gcc -L looks in directory for library files.

$ gcc [options] [source files] [object
											files] [-Ldir] -llibname  [-o outfile]

Link -l with library name without the lib prefix and the .a or .so extensions.

							Example1

For static library file libmath.a use -lmath:

$ gcc -static myfile.c -lmath -o myfile

For shared library file libmath.so use -lmath:

$ gcc myfile.c -lmath -o myfile

							Example3

file1.c:

// file1.c #include  void main() {
									     printf("main() run!\n");     myfunc(); }

file2.c:

// file2.c #include  void myfunc() {
									     printf("myfunc() run!\n"); }

Build file2.c, copy object file file2.o to libs directory and archive it to static library libmylib.a:

$ gcc -c file2.c $ mkdir libs $ cp file2.o libs $ cd libs $ ar rcs libmylib.a file2.o

Build file1.c with static library libmylib.a in libs directory.

Build without -L results with an error:

$ gcc file1.c -lmylib -o outfile /usr/bin/ld: cannot find -llibs collect2: ld returned 1 exit status $

Build with -L and run:

$ gcc file1.c -Llibs -lmylib -o outfile $ ./outfile main() run! myfunc() run! $